private function getNeededTransactions(ConpherenceThread $conpherence, $message_id)
{
if ($message_id) {
$newer_transactions = $conpherence->getTransactions();
$query = id(new ConpherenceTransactionQuery())->setViewer($this->getRequest()->getUser())->withObjectPHIDs(array($conpherence->getPHID()))->setAfterID($message_id)->needHandles(true)->setLimit(self::OLDER_FETCH_LIMIT);
$older_transactions = $query->execute();
$handles = array();
foreach ($older_transactions as $transaction) {
$handles += $transaction->getHandles();
}
$conpherence->attachHandles($conpherence->getHandles() + $handles);
$transactions = array_merge($newer_transactions, $older_transactions);
$conpherence->attachTransactions($transactions);
} else {
$transactions = $conpherence->getTransactions();
}
return $transactions;
}